If statement in reqular sql statement

Question

Hi everyone;
I am trying to alter some trigger if I am in a certain environment. here what I am trying to do in pseudo-code
if ((select dbenv from environments) = 'DEV') THEN
ALTER TRIGGER XXX disable;
end if;
this sql script will be run from sqlplus' comand line
reminder I don't want to do that from package or a procedure

Answer 1

this to just explain
i think select in the IF is not allowed that way please see the examples below
SQL> ed
Wrote file afiedt.buf
  1  DECLARE
  2  vename VARCHAR2(10);
  3  BEGIN
  4   SELECT ename INTO vename FROM EMP WHERE ename='BLAKE';
  5   IF vename='BLAKE' THEN
  6    DBMS_OUTPUT.PUT_LINE('data found');
  7   ELSE
  8     DBMS_OUTPUT.PUT_LINE('no data found');
  9   END IF;
10* END;
11  /
data found
PL/SQL procedure successfully completed.
SQL> ed
Wrote file afiedt.buf
  1  DECLARE
  2  vename VARCHAR2(10);
  3  BEGIN
  4   --SELECT ename INTO vename FROM EMP WHERE ename='SMITH';
  5   IF ((SELECT ename FROM EMP WHERE ename ='SMITH')='BLAKE') THEN
  6    DBMS_OUTPUT.PUT_LINE('data found');
  7   ELSE
  8     DBMS_OUTPUT.PUT_LINE('no data found');
  9   END IF;
10* END;
SQL> /
IF ((SELECT ename  FROM EMP WHERE ename ='SMITH')='BLAKE') THEN
ERROR at line 5:
ORA-06550: line 5, column 7:
PLS-00103: Encountered the symbol "SELECT" when expecting one of the following:
( - + case mod new not null others <an identifier>
<a double-quoted delimited-identifier> <a bind variable> avg
count current exists max min prior sql stddev sum variance
execute forall merge time timestamp interval date
<a string literal with character set specification>
<a number> <a single-quoted SQL string> pipe
ORA-06550: line 5, column 50:
PLS-00103: Encountered the symbol ")" when expecting one of the following:
. ( * @ % & - + ; / at for mod rem <an exponent (**)> and or
group having intersect minus order start union where connect
||
but this is allowed
SQL> ed
Wrote file afiedt.buf
  1  DECLARE
  2  vename VARCHAR2(10);
  3  BEGIN
  4   --SELECT ename INTO vename FROM EMP WHERE ename='SMITH';
  5   IF 'BLAKE'='BLAKE' THEN
  6     SELECT ename INTO vename FROM EMP WHERE ename='SMITH';
7    DBMS_OUTPUT.PUT_LINE(vename);
  8   ELSE
  9     DBMS_OUTPUT.PUT_LINE('no data found');
10   END IF;
11* END;
SQL> /
SMITH
PL/SQL procedure successfully completed.formated
Message was edited by:
devmiral